Conventionally, a developing apparatus which uses a two-component developer composed of a toner and a carrier and an image forming apparatus which forms an image by using the developing apparatus have been widely known. By stirring the two-component developer inside a developing tank, the developing apparatus generates friction between the toner and the carrier to thereby charge the toner. The charged toner is supplied to a surface of a developing roller and moved from the developing roller to an electrostatic latent image formed on a surface of a photoreceptor drum by electrostatic attraction force. Thereby, a toner image based on the electrostatic latent image is formed on the photoreceptor drum. This toner image is transferred and fixed onto a recording medium, so that an image is formed on the recording medium.
In recent years, speeding-up and miniaturization of the image forming apparatus are required, and accordingly it is necessary to perform charging of developer promptly and sufficiently as well as to perform conveyance of the developer promptly. As a technology therefor, in Patent Literature 1, proposed is a circulation type developing apparatus in which a partition wall is provided inside a developing tank, the developing tank is divided by this partition wall into a first developer conveying path and a second developer conveying path which extend along a longitudinal direction of the partition wall and are opposed to each other with the partition wall interposed therebetween and a first communication path and a second communication path with which the first developer conveying path and the second developer conveying path are communicated in both sides of the longitudinal direction of the partition wall, and a first auger screw and a second auger screw which are conveying members for conveying the developer are disposed in the first developer conveying path and in the second developer conveying path.